EP2408023A1 - Thin-film Solar Fabrication Process, Deposition method for TCO layer, and Solar cell precursor layer stack - Google Patents
Thin-film Solar Fabrication Process, Deposition method for TCO layer, and Solar cell precursor layer stack Download PDFInfo
- Publication number
- EP2408023A1 EP2408023A1 EP10169889A EP10169889A EP2408023A1 EP 2408023 A1 EP2408023 A1 EP 2408023A1 EP 10169889 A EP10169889 A EP 10169889A EP 10169889 A EP10169889 A EP 10169889A EP 2408023 A1 EP2408023 A1 EP 2408023A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- layer
- alkali metal
- substrate
- tco
- depositing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
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- H—ELECTRICITY
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- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/40—Coatings comprising at least one inhomogeneous layer
- C03C2217/42—Coatings comprising at least one inhomogeneous layer consisting of particles only
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/70—Properties of coatings
- C03C2217/77—Coatings having a rough surface
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2217/00—Coatings on glass
- C03C2217/90—Other aspects of coatings
- C03C2217/94—Transparent conductive oxide layers [TCO] being part of a multilayer coating
- C03C2217/944—Layers comprising zinc oxide
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2218/00—Methods for coating glass
- C03C2218/30—Aspects of methods for coating glass not covered above
- C03C2218/31—Pre-treatment
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- C—CHEMISTRY; METALLURGY
- C03—GLASS; MINERAL OR SLAG WOOL
- C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
- C03C2218/00—Methods for coating glass
- C03C2218/30—Aspects of methods for coating glass not covered above
- C03C2218/32—After-treatment
- C03C2218/328—Partly or completely removing a coating
- C03C2218/33—Partly or completely removing a coating by etching
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
- H01L31/072—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PN heterojunction type
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L31/00—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L31/04—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices
- H01L31/06—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier
- H01L31/075—Semiconductor devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation and specially adapted either for the conversion of the energy of such radiation into electrical energy or for the control of electrical energy by such radiation; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof adapted as photovoltaic [PV] conversion devices characterised by at least one potential-jump barrier or surface barrier the potential barriers being only of the PIN type
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/547—Monocrystalline silicon PV cells
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
- Y02E10/548—Amorphous silicon PV cells
Abstract
Methods of depositing a TCO layer on a substrate and precursor for solar cells are described. A method of depositing a TCO layer (404) on a substrate (102) includes providing a glass substrate having a first alkali metal concentration, conditioning the glass substrate, wherein the conditioning comprises at least one step selected from the group consisting of: applying a liquid to the substrate to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a layer to form a layer (402) with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a TCO layer (404) over the conditioned substrate.
Description
- Embodiments of the present invention generally relate to depositing TCO layers and texturing TCO layers, which are deposited on a conditioned substrate, particularly for a front contact surface of solar cells. Specifically, they relate to a method of depositing a TCO layer on a substrate and a precursor for a solar cell device.
- Crystalline silicon solar cells and thin-film solar cells are two types of solar cells. Crystalline silicon solar cells typically use either monocrystalline substrates (i.e., single-crystal substrates of pure silicon) or multi-crystalline silicon substrates (i.e., poly-crystalline or polysilicon). Additional film layers are deposited onto the silicon substrates to improve light capture, form the electrical circuits, and protect the devices. Thin-film solar cells use thin layers of materials deposited on suitable substrates to form one or more p-n junctions. Suitable substrates include glass, metal, and polymer substrates.
- To expand the economic uses of solar cells, efficiency must be improved. Solar cell stabilized efficiency relates to the proportion of incident radiation converted into usable electricity. For solar cells to be useful for more applications, solar cell efficiency must be improved beyond the current best performance of approximately 10% for Si based Thin-film solar modules. With energy costs rising, there is a need for improved thin-film solar cells and methods and apparatuses for forming the same in a factory environment.
- In order to improve the efficiency of a solar cell, light trapping is one aspect that can be improved. In order to improve trapping of the photons surface texture at the light entering surface can be utilized.
- Another aspect for improving mass production of solar cells is the use of large scale processes and the reliability at which processes can be conducted. Thus, there is a desire to improve the processes for increasing the efficiency on a large scale and for applications during industrial manufacturing.
- In light of the above, a method of depositing a TCO layer on a substrate according to
independent claim 1 and a precursor for a solar cell according to independent claim 7 are provided. - Embodiments of the invention provide methods of depositing TCO layers and texturing TCO layers, which are deposited on a conditioned substrate. According to one embodiment a method of depositing a TCO layer on a substrate is provided. The method includes providing a glass substrate having a first alkali metal concentration and conditioning the glass substrate, wherein the conditioning comprises at least one step selected from the group consisting of: applying a liquid to the substrate to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a layer to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration. The method further includes depositing a TCO layer over the conditioned substrate.
- According to another embodiment a method of depositing a TCO layer on a substrate is provided. The method includes providing a glass substrate and conditioning the glass substrate, wherein the conditioning includes at least one step selected from the group consisting of: cleaning the substrate or applying a liquid to the substrate to form an alkali metal-containing seed layer, and depositing a layer to form an alkali metal-containing seed layer. The method further comprises depositing a TCO layer over the conditioned substrate.
According to a yet further embodiment a precursor for a solar cell is provided. The precursor includes a glass substrate, an alkali metal-containing seed layer provided on the glass substrate, and a TCO layer deposited over the seed layer. - So that the manner in which the above recited features of the present invention are attained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof, which are illustrated in the appended drawings.
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Figure 1 is a schematic side-view of a tandem junction thin-film solar cell according to one embodiment of the invention; -
Figure 2 is a schematic side-view of a single junction thin-film solar cell according to one embodiment of the invention; -
Figures 3A and 3B are schematic side-views of a front surface of a semiconductor precursor illustrating light trapping, which can for example be utilized for a solar cell. -
Figures 4A to 4F illustrate the layers deposited on a substrate according to embodiments described herein; -
Figure 5 is a schematic flow chart of a method of depositing a TCO on a substrate according to embodiments described herein; -
Figures 6A to 6E illustrate a yet further embodiment of a layer stack of layers deposited on a substrate according to embodiments described herein; -
Figure 7 is a schematic flow chart of a yet further method of depositing a TCO on a substrate according to embodiments described herein; -
Figure 8 is a schematic side view illustrating an apparatus for depositing a layer stack according to embodiments described herein and for conducting a method according to embodiments described herein; and -
Figures 9 and10 are schematic side views illustrating a yet further apparatuses for depositing a layer stack according to embodiments described herein and for conducting a method according to embodiments described herein. - To facilitate understanding, identical reference numerals have been used, where possible, to designate identical or similar elements that are common to the figures. It is contemplated that elements and features of one embodiment may be beneficially incorporated into other embodiments without further recitation.
- It is to be noted, however, that the appended drawings illustrate only exemplary embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments.
- Reference will now be made in detail to the various embodiments of the invention, one or more examples of which are illustrated in the figures. Each example is provided by way of explanation of the invention and is not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with other embodiments to yield yet a further embodiment. It is intended that the present invention includes such modifications and variations.
- The term "substrate" as used herein shall embrace both inflexible substrates, e.g. a wafer or a glass plate, and flexible substrates such as webs and foils.
- Embodiments described herein relate to processes for the etching of substrate precursors, a method of forming solar cells including etching of substrate precursors, devices for etching substrate precursors, and layer stacks for solar cells being based on substrate precursors with etching processes as described herein. Thereby, reference is for example made to the solar cells as described below and explained in further detail with respect to
Figs. 1 and 2 . - Thin-film solar cells are generally formed from numerous types of films, or layers, combined in many different ways. Most films used in such devices incorporate a semiconductor element that may comprise silicon, germanium, carbon, boron, phosphorous, nitrogen, oxygen, hydrogen and the like. Characteristics of the different films include degree of crystallinity, dopant type, dopant concentration, film refractive index, film extinction coefficient, film transparency, film absorption, and conductivity. Typically, most of these films can be formed by use of a chemical vapor deposition process, which may include some degree of ionization, plasma formation, and/or sputtering processes.
- Sputtering is a process in which atoms are ejected from a solid target material due to the bombardment of the target by energetic particles. The process of coating a substrate as a material at the scraping refers typically to thin-film applications. The term "coating" and the term "depositing" are used synonymously herein. The terms "sputtering installation" and "deposition apparatus" are used synonymously herein and shall embrace for example an apparatus which uses sputtering for depositing a target material, typically as a thin-film, on a substrate. Typical target materials include (but are not limited to) pure metals such as aluminum (Al), copper (Cu), silver (Ag) and gold (Au), metal alloys such as an aluminum-niobium (AINb) alloy or an aluminum-nickel (AINi) alloy, semiconductor materials such as silicon (Si) and dielectric materials such as nitrides, carbides, titanates, silicates, aluminates and oxides, e.g. transparent conducting oxides (TCO) such as impurity-doped ZnO, In2O3, SnO2 and CdO, as well as Sn doped In2O3 (ITO) and F doped SnO2.
- According to different embodiments, a plurality of films can be used in solar cells. Charge generation during a photovoltaic process is generally provided by a bulk semiconductor layer, such as a silicon-containing layer. The bulk layer is also sometimes called an intrinsic layer to distinguish it from the various doped layers present in the solar cell. The intrinsic layer may have any desired degree of crystallinity, which will influence its light-absorbing characteristics. For example, an amorphous intrinsic layer, such as amorphous silicon, will generally absorb light at different wavelengths from intrinsic layers having different degrees of crystallinity, such as microcrystalline silicon. For this reason, most solar cells will use both types of layers to yield the broadest possible absorption characteristics. In some instances, an intrinsic layer may be used as a buffer layer between two dissimilar layer types to provide a smoother transition in optical or electrical properties between the two layers.
- Silicon and other semiconductors can be formed into solids having varying degrees of crystallinity. Solids having essentially no crystallinity are amorphous, and silicon with negligible crystallinity is referred to as amorphous silicon. Completely crystalline silicon is referred to as crystalline, polycrystalline, or monocrystalline silicon. Polycrystalline silicon is crystalline silicon formed into numerous crystal grains separated by grain boundaries. Monocrystalline silicon is a single crystal of silicon. Solids having partial crystallinity, that is a crystal fraction between about 5% and about 95%, are referred to as nanocrystalline or microcrystalline, generally referring to the size of crystal grains suspended in an amorphous phase. Solids having larger crystal grains are referred to as microcrystalline, whereas those with smaller crystal grains are nanocrystalline. It should be noted that the term "crystalline silicon" may refer to any form of silicon having a crystal phase, including microcrystalline and nanocrystalline silicon.
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FIG. 1 is a schematic diagram of an embodiment of a multi-junctionsolar cell 100 oriented toward the light orsolar radiation 101.Solar cell 100 comprises asubstrate 102, such as a glass substrate, polymer substrate, metal substrate, or other suitable substrate, with thin-films formed thereover. Thesolar cell 100 further comprises a first transparent conducting oxide (TCO)layer 104 formed over thesubstrate 102, and a firstp-i-n junction 126 formed over thefirst TCO layer 104. In one configuration, a wavelength selective reflector (WSR)layer 112 is formed over the firstp-i-n junction 126. A secondp-i-n junction 128 is formed over the firstp-i-n junction 126, asecond TCO layer 122 is formed over the secondp-i-n junction 128, and a metal backlayer 124 is formed over thesecond TCO layer 122. In one embodiment, aWSR layer 112 is disposed between the firstp-i-n junction 126 and the secondp-i-n junction 128, and is configured to have film properties that improve light scattering and current generation in the formedsolar cell 100. Additionally, theWSR layer 112 also provides a good p-n tunnel junction that has a high electrical conductivity and a tailored bandgap range that affects its transmissive and reflective properties to improve the formed solar cell's light conversion efficiency. - To improve light absorption by enhancing light trapping, the substrate and/or one or more of the thin-films formed thereover may be optionally textured by wet, plasma, ion etching, and/or mechanical processes. For example, in the embodiment shown in
FIG. 1 , thefirst TCO layer 104 is textured and the subsequent thin-films deposited thereover will generally follow the topography of the surface below it. - Thereby, according to some embodiments described herein, the
substrate 102 is conditioned to provide improved properties of the TCO layer, such as a ZnO-containing layer. The conditioning can include increasing a alkali metal content of the substrate before depositing the TCO layer. Thereby, nucleation of the TCO layer can be influenced to provide for improved texturing and to provide desired electrical and optical properties of the TCO layer. According to some embodiments, the conditioning can be conducted by depositing or preparing an alkali metal-containingseed layer 103. - The
first TCO layer 104 and thesecond TCO layer 122 may each comprise tin oxide, zinc oxide, indium tin oxide, cadmium stannate, combinations thereof, or other suitable materials. It is understood that the TCO materials may also include additional dopants and components. For example, zinc oxide may further include dopants such as aluminum, gallium, boron, and other suitable dopants. Zinc oxide preferably includes 5 atomic % or less of dopants, and more preferably comprises 2.5 atomic % or less aluminum. In certain instances, thesubstrate 102 may be provided by the glass manufacturers with thefirst TCO layer 104 already provided. - The first
p-i-n junction 126 may comprise a p-typeamorphous silicon layer 106, an intrinsic typeamorphous silicon layer 108 formed over the p-typeamorphous silicon layer 106, and an n-typemicrocrystalline silicon layer 110 formed over the intrinsic typeamorphous silicon layer 108. In certain embodiments, the p-typeamorphous silicon layer 106 may be formed to a thickness between about 60Å and about 300Å. In certain embodiments, the intrinsic typeamorphous silicon layer 108 may be formed to a thickness between about 1,500Å and about 3,500Å. In certain embodiments, the n-typemicrocrystalline semiconductor layer 110 may be formed to a thickness between about 100Å and about 400Å. - The
WSR layer 112 disposed between the firstp-i-n junction 126 and the secondp-i-n junction 128 is generally configured to have certain desired film properties. In this configuration theWSR layer 112 actively serves as an intermediate reflector having a desired refractive index, or ranges of refractive indexes, to reflect light received from the light incident side of thesolar cell 100. TheWSR layer 112 also serves as a junction layer that boosts the absorption of the short to mid wavelengths of light (e.g., 280nm to 800nm) in the firstp-i-n junction 126 and improves short-circuit current, resulting in improved quantum and conversion efficiency. Further, theWSR layer 112 has high film transmittance for mid to long wavelengths of light (e.g., 500nm to 1100nm) to facilitate the transmission of light to the layers formed in thejunction 128. Further, it is generally desirable for theWSR layer 112 to absorb as little light as possible while reflecting desirable wavelengths of light (e.g., shorter wavelengths) back to the layers in the firstp-i-n junction 126 and transmitting desirable wavelengths of light (e.g., longer wavelengths) to the layers in the secondp-i-n junction 128. - In one embodiment, the
WSR layer 112 may comprise an n-type doped silicon alloy layer, such as silicon oxide (SiOx, SiO2) silicon carbide (SiC), silicon oxynitride (SiON), silicon nitride (SiN), silicon carbon nitride (SiCN), silicon oxycarbide (SiOC), silicon oxycarbon nitride (SiOCN), or the like. In an exemplary embodiment, theWSR layer 112 is an n-type SiON or SiC layer. - The second
p-i-n junction 128 may comprise a p-typemicrocrystalline silicon layer 114 and, in some cases, an optional p-i buffer type intrinsic amorphous silicon (PIB)layer 116 that is formed over the p-typemicrocrystalline silicon layer 114. Subsequently, an intrinsic typemicrocrystalline silicon layer 118 is formed over the p-typemicrocrystalline silicon layer 114, and an n-typeamorphous silicon layer 120 is formed over the intrinsic typemicrocrystalline silicon layer 118. In certain embodiments, the p-typemicrocrystalline silicon layer 114 may be formed to a thickness between about 100Å and about 400Å. In certain embodiments, the p-i buffer type intrinsic amorphous silicon (PIB)layer 116 may be formed to a thickness between about 50 Å and about 500 Å. In certain embodiments, the intrinsic typemicrocrystalline silicon layer 118 may be formed to a thickness between about 10,000Å and about 30,000Å. In certain embodiments, the n-typeamorphous silicon layer 120 may be formed to a thickness between about 100Å and about 500Å. - The metal back
layer 124 may include, but is not limited to a material selected from the group consisting of Al, Ag, Ti, Cr, Au, Cu, Pt, alloys thereof, or combinations thereof. Other processes may be performed to form thesolar cell 100, such as one or more laser scribing processes. Other films, materials, substrates, and/or packaging may be provided over the metal backlayer 124 to complete the solar cell device. The formed solar cells may be interconnected to form modules, which in turn can be connected to form arrays. -
Solar radiation 101 is primarily absorbed by theintrinsic layers p-i-n junctions type layer type layer intrinsic layer type layers type layers p-i-n junction 126 comprises an intrinsic typeamorphous silicon layer 108 and the secondp-i-n junction 128 comprises an intrinsic typemicrocrystalline silicon layer 118 since amorphous silicon and microcrystalline silicon absorb different wavelengths of thesolar radiation 101. Therefore, the formedsolar cell 100 is more efficient, since it captures a larger portion of the solar radiation spectrum. Theintrinsic layer solar radiation 101 first strikes the intrinsic typeamorphous silicon layer 118 and is transmitted through theWSR layer 112 and then strikes the intrinsic typemicrocrystalline silicon layer 118 since amorphous silicon has a larger bandgap than microcrystalline silicon. Solar radiation not absorbed by the firstp-i-n junction 126 continuously transmits through theWSR layer 112 and continues to the secondp-i-n junction 128. - Charge collection is generally provided by doped semiconductor layers, such as silicon layers doped with p-type or n-type dopants. P-type dopants are generally group III elements, such as boron or aluminum. N-type dopants are generally group V elements, such as phosphorus, arsenic, or antimony. In most embodiments, boron is used as the p-type dopant and phosphorus as the n-type dopant. These dopants may be added to the p-type and n-
type layers -
FIG. 2 is a schematic side-view of a double-junction thin-filmsolar cell 200 according to other embodiments of the invention, which might in some instances use a light trapping improvement. The embodiment ofFIG. 2 differs from that ofFIG. 1 by inclusion of a p-type crystallinesilicon alloy layer 206 between the p-typeamorphous silicon layer 208 and thefirst TCO layer 104 ofFIG. 1 . Alternatively, the p-type crystallinesilicon alloy layer 206 may be a degeneratively doped layer having p-type dopants heavily doped in thealloy layer 206. The embodiment ofFIG. 2 thus comprises thesubstrate 102 on which aconductive layer 204, such as a TCO layer similar to thefirst TCO layer 104 ofFIG. 1 , is formed. As described above, a p-type crystallinesilicon alloy layer 206 is formed over theconductive layer 204. The p-type crystallinesilicon alloy layer 206 has improved bandgap due to lower doping, an adjustable refractive index generally lower than that of a degeneratively doped layer, high conductivity, and resistance to oxygen attack by virtue of the included alloy components. Ap-i-n junction 220 is formed over the p-type crystallinesilicon alloy layer 206 by forming a p-typeamorphous silicon layer 208, aPIB layer 210, an intrinsicamorphous silicon layer 212, and an n-typeamorphous silicon layer 214. Thesolar cell 200 ofFIG. 2 is completed, similarly to the foregoing embodiments, with an n-type crystallinesilicon alloy layer 216, which is similar to theWSR layer 112 ofFIG. 1 , and a second conductive layer 218, which may be a metal or metal/TCO stack, similar to theconductive layers FIG. 1 . - According to different embodiments, a plurality of methods and system/apparatus configurations for texturing a semiconductor precursor can be utilized in embodiments described herein. As described above, the layers, particularly the
TCO layer 104, are generally textured in order to improve light trapping and, thus, the efficiency of a solar cell. In the following, it is exemplarily referred to etching of zinc oxide (ZnO) layers as a front contact of precursors for a solar thin-film. However, the same principles can be applied to other semiconductor device manufacturing methods. - According to some embodiments described herein, the
substrate 102 is conditioned to provide improved properties of the TCO layer, such as a ZnO-containing layer. The conditioning can include increasing a alkali metal content of the substrate before depositing the TCO layer. Thereby, nucleation of the TCO layer can be influenced to provide for improved texturing and to improve the desired electrical and optical properties of the TCO layer. According to some embodiments, the conditioning can be conducted by depositing or preparing an alkali metal-containingseed layer 103. - As illustrated with respect to
FIGS. 3A and 3B , texturing of layers or films in the semiconductor device can, for example, improve light trapping.FIGS. 3A and 3B show thesemiconductor device precursor Layers substrate 102. As shown inFIG. 3A , the layer 302 has a flat or almost flat upper surface. In light thereof, a portion of aradiation source 101, such as the sun for a solar cell device, can be reflected within the semiconductor device precursor. This is indicated by a portion of the photons being reflected at the upper surface oflayer 304A inFIG. 3A . Thereby, the photons can leave the layer stack for a solar cell after a relative short path length. Contrary thereto, as shown inFIG. 3B , atextured surface 302B increases the likelihood of all, or at least 90 %, of the photons to enter the semiconductor device. Further, the photons are diffracted at the boundaries of the layers such that the photons might even remain in one layer by total internal reflection upon diffraction at the textured TCO layer. Thereby, the path length within the desired layer in which photons should be absorbed for light conversion is increased. This generally improves the efficiency of the layer stack for the solar cell. - According to embodiments described herein, an improved ZnO-containing TCO layer is deposited on an industrially-relevant scale. For example, the TCO layers of some embodiments described herein can be deposited on an area of 3 m2 and above, 4 m2 and above, or 5 m2 and above. Thereby, the surface on which the ZNO-containing TCO layer is to be deposited is conditioned to provide a desired nucleation area for the desired film properties. According to typical examples, alkali metals, such as Na and K, can be found in the ZnO nucleation area. Typically, these elements, which may also, in some quantity, be included in the substrate itself, can provide a seed or a seed layer. Accordingly, the cleaning process, the choice of detergent for a cleaning process or a deposition step of a seed layer can be provided such that alkali metal-containing seeds are provided.
- Thus, according to some embodiments described herein, alkali metal contamination can be introduced during a deposition step, or can remain on the substrate.
- Thereby, according to different alternatives, the alkali metal-containing seeds or the desired alkali metal concentration can be provided on the substrate before or after cleaning, on a barrier layer or by a barrier layer, which is deposited between the substrate and the TCO layer.
- Embodiments described herein are thereby generally related to the front contact, particularly of a thin-film solar cell, such as a silicon thin-film solar cell. Further, seeds or a seed layer is provided due to the cleaning of the flat glass substrates, e.g. by means of the detergent, or due to deposition of the seeds or the seed layer.
- The inventors have found, that the structure or cleanliness with regard to the alkali metal concentration of the surface to be coated with the ZnO-containing layer influences the growth structure of the ZnO-containing layer. Thereby, a different ZnO structure after the texturing, e.g. by an etching step, can be provided. Thereby, optimizing the nucleation of the ZnO layer also needs to take into account the electrical and optical properties of the TCO layer in order to realize high efficiency of a solar cell module, improved light trapping, long lifetime under environmental conditions, cost-effectiveness and repeatability of manufacturing, and the like.
- Typical embodiments are, for example, shown in
FIGS. 4A to 4F , which are described in the following while referring to the method illustrated inFIG. 5 .FIG. 4A shows asubstrate 102 which can be provided for depositing a TCO layer. According to some embodiments, the TCO layer can be used as a front contact layer of a thin-film solar cell. In step 502 a barrier layer is deposited on the substrate. This is illustrated bylayer 402 shown inFIG. 4B . As shown inFIG. 4C , thebarrier layer 402 is conditioned such that aseed layer 410 or corresponding seeds are provided on the barrier layer. - Thereby, according to different embodiments, which can be used alternatively to each other or in combination with each other, the
conditioning step 504 provides a defined concentration of alkali metals on the surface on which the zinc oxide layer 404 (seeFIG. 4D ) is deposited. Typically, the alkali metal concentration can be provided during the deposition step of thebarrier layer 402, during a cleaning step of thesubstrate 102, on which thebarrier layer 402 might or might not be deposited, and combinations thereof. Thereby, the alkali metal-containingseed layer 410 can have a thickness of 5 nm or below or can be even less than 1 nm. Accordingly, even though reference is made to alayer 410, the seed layer might not be a fully closed layer but might be a plurality of seeds or seed islands. It is to be understood that a thin layer with a thickness of only a few atoms will not continuously grow over the entire surface. Typically, the nucleation of a layer starts at several positions on a surface and a few atomic layers might build up in areas around those positions before the entire layer covers the surface to be coated. Thus, according to embodiments described herein, a seed layer might not necessarily fully cover the surface below. - According to yet further embodiments, the alkali metal can be sodium, potassium, or mixtures thereof. Thereby, typically the alkali metal element concentration, particularly the Na concentration, in the layer can be increased by at least 50%, typically by at least 100%, i.e. the number of alkali metal atoms is increased by at least 50%, typically by at least 100%. According to yet further alternative for additional embodiments, alkali metal atoms can be present at the conditioned surface with 1x1013 to 1x1018 atoms per cm2.
- After the layer stack has been conditioned in
step 504, the TCO layer, typically a ZnO-containing layer, is deposited on the layer stack. Accordingly, the solar cell precursor shown inFIG. 4D is provided afterstep 506. Instep 508, the TCO layer is textured resulting in the solar cell precursor shown inFIG. 4E . - According to some embodiments, which can be combined with other embodiments described herein, the solar cell precursors, the methods and devices for etching semiconductor device precursors, such as solar cell precursors, can be utilized for large area thin-films. For example, substrate sizes of 1.43 m2 (Gen5) and above such as 5.7 m2 (Gen8.5) or larger can be realized. Further typical embodiments relate to aluminum doped zinc oxide layers (ZnO:Al) as a TCO, which can be sputtered from rotatable ceramic zinc oxide aluminum oxide (ZnO:A1203) targets. Typically, the aluminum doped zinc oxide layers form a front contact of a solar cell. According to yet further embodiments, the TCO layer can be wet-chemically etched, for example in diluted hydrochloric acid, or other suitable etchants. Thereby, as described above, the etching process is of importance for the surface texture, which is used to scatter the light, particularly the long wavelength light in the VIS and NIR range.
- Typically, the shape and feature size of the etched semiconductor layer depends on the parameters of the layer as well as the etching process. Accordingly, for a predetermined semiconductor layer with certain characteristics, the nucleation of the layer to be etched needs to be controlled such that the desired texture of the layer is generated.
- According to different embodiments, the texturing can be conducted by a wet etching process or a dry etching process. According to yet further implementations, the etching process can be an isotropic or an anisotropic etching process. Typically, the
texturing step 508 can be provided by etching the zinc oxide-containing TCO layer with a diluted acid in order to roughen the ZnO surface by wet etching. Thereby, as described with respect toFIGS. 3A and 3B , a specific haze is desired in order to improve light trapping of the layer stack for manufacturing a thin-film solar cell. - After texturing the TCO layer in
step 508, asilicon layer 406 is deposited instep 510. According to typical embodiments, the silicon layer can be a p-type silicon layer, for example a p-typeamorphous silicon layer 106 shown inFIG. 1 . Alternatively, a p-typecrystalline silicon layer 206 shown inFIG. 2 can be deposited on thetextured TCO layer 414. Generally, one or more p-n-junctions are deposited on the TCO layer. Thereby, thetextured TCO layer 414 forms the front contact of a precursor of a thin-film solar cell. - Generally, glass has a high sodium (Na) concentration and a low potassium (K) concentration. On the glass surface of the substrate, in comparison to the glass volume, the Na concentration is depleted near the surface and can be increased within the first few nm of an untreated glass substrate. By conditioning the layer stack before deposition of the ZnO-containing
TCO layer 404, i.e. by providing the seeds or theseed layer 410, an alkali metal-containing layer is provided over the surface of a standard glass substrate, wherein the alkali metal layer concentration is higher as compared to the surface concentration of the glass substrate without the conditioning step. - Thereby, according to typical embodiments, which can be combined with other embodiments described herein, the Na and the K concentration can be increased. In the event of an untreated glass substrate, particularly the K concentration can be increased by at least 50%, typically by at least 100%, whereas the Na concentration might be increased to a smaller degree. Yet further, if the glass substrate is polished such that the alkali element concentration corresponds to the concentration of the depletion zone before conditioning of the substrate, both the Na and the K concentration can be increased by at least 50%, typically by at least 100%.
- According to yet further embodiments, which are illustrated in
FIGS. 6A to 6D and the flowchart shown inFIG. 7 , asubstrate 102 can be provided in step 702. Insteps substrate 102 in order to provide the desired alkali metal concentration can be provided without a previously deposited barrier layer. Thereby, aseed layer 610 is provided on thesubstrate 102 as shown inFIG. 6B . According to alternative or additional embodiments, the seeds or the seed layer can be provided by cleaning the substrate (see step 704) or by depositing the seeds or the seed layer (see step 706). - According to one embodiment, conditioning of the surface on which the zinc oxide-containing TCO layer is to be deposited can be provided by cleaning the substrate or the layer stack with a detergent. Typically, the detergent for cleaning the substrate can be an alkali base and can, for example, include sodium hydroxide and/or potassium hydroxide. Thereby, the alkali metal concentration on the surface on which the TCO layer is to be deposited is increased and can be controlled.
- According to further additional or alternative modifications, the alkali metal-containing
seed layer 610 can also be deposited on thesubstrate 102 as shown instep 706. According to yet further embodiments, the alkali metal can be sodium, potassium, or mixtures thereof. Thereby, typically the alkali metal element concentration, particularly the Na concentration, in the layer can be increased by at least 50%, typically by at least 100%, i.e. the number of alkali metal atoms is increased by at least 50%, typically by at least 100%. According to yet further alternative for additional embodiments, alkali metal atoms can be present at the conditioned surface with 1x1013 to 1x1018 atoms per cm2. - In
step 708 the zinc oxide-containing TCO layer is deposited, which results in theTCO layer 604 shown inFIG. 6C . According to some embodiments, which can be combined with other embodiments described herein, this can be utilized for wet etching of metal oxides, such as zinc oxide. Thereby, according to some embodiments, which can be combined with other embodiments described herein, a layer thickness of 400 - 1200 nm of a semiconductor layer to be etched can be provided. - The nucleation of the TCO layer on the conditioned surface is such that a
texturing step 710 results in thetextured TCO layer 614, which provides sufficient haze for light trapping. This is, for example, advantageous for the efficiency of a thin-film solar cell. - According to different embodiments, the texturing can be conducted by a wet etching process or a dry etching process. According to yet further implementations, the etching process can be an isotropic or an anisotropic etching process. Typically, the
texturing step 508 can be provided by etching the zinc oxide-containing TCO layer with a diluted acid in order to roughen the ZnO surface by wet etching. Thereby, as described with respect toFIGS. 3A and 3B , a specific haze is desired in order to improve light trapping of the layer stack for manufacturing a thin-film solar cell. - After texturing the TCO layer in
step 710, a silicon layer 606 is deposited. According to typical embodiments, the silicon layer can be a p-type silicon layer, for example a p-typeamorphous silicon layer 106 as shown inFIG. 1 . Alternatively, a p-typecrystalline silicon layer 206 as shown inFIG. 2 can be deposited on thetextured TCO layer 614. Generally, one or more p-n-junctions are deposited on the TCO layer. Thereby, thetextured TCO layer 614 forms the front contact of a precursor of a thin-film solar cell. -
FIG. 8 illustrates an apparatus for depositing a TCO layer according to embodiments described herein. Theapparatus 800 includes two ormore chambers 830 or respective compartments. A transport system with, for example,rollers 832 for transporting asubstrate 801 through thesystem 800 is provided. Typically, the chambers haveopenings 831 for introducing thesubstrate 801 into the chamber and transferring the substrate into a subsequent chamber or out of the chamber. According to typical embodiments, theopenings 831 can be sealed with valves during operation of thesystem 800. - As shown in
FIG. 8 ,nozzles 842 for spraying a detergent on thesubstrate 801 can be provided in the first chamber of thechambers 830. According to alternatives embodiments, the cleaning step with a detergent can also be conducted in a bath. The substrate or the layer stack being cleaned in the left chamber of thesystem 800 shown inFIG. 8 , is conditioned with alkali metal seeds or an alkali metal seed layer, is transported towards thesecond chamber 830, whereby for example a drying process might be conducted, and is transferred into thesecond chamber 830. The second chamber includes sputteringcathodes 852, such as rotatable sputtering cathodes, for sputtering the TCO layer, such as a zinc oxide layer, on thesubstrate 801. Thereby, a TCO layer, which can be textured in the subsequence processing step such as a wet etching step, is deposited over the substrate. -
FIG. 9 illustrates a yet further embodiment of an apparatus for depositing a TCO layer according to embodiments described herein. Theapparatus 900 includes two ormore chambers rollers 832 for transporting asubstrate 801 through thesystem 800 is provided. Typically, the chambers haveopenings 831 for introducing thesubstrate 801 into the chamber and transferring the substrate into a subsequent chamber or out of the chamber. According to typical embodiments, theopenings 831 can be sealed with valves during operation of thesystem 800. As shown inFIG. 9 , in the first chamber of thechambers 830, sputtercathodes 952, such as rotatable sputter cathodes can be provided to deposit a barrier layer or a seed layer, such that an alkali metal concentration is controlled and increased as compared to the surface concentration of the glass substrate. According to alternative implementations, the seeds or the seed layer can also be provided by a CVD process, such as a PECVD process. After the substrate or the layer stack has been conditioned in the left chamber of thesystem 900 shown inFIG. 9 with alkali metal seeds or an alkali metal seed layer, the substrate is transferred in thesecond chamber 830. The second chamber includes sputteringcathodes 852, such as rotatable sputtering cathodes, for sputtering the TCO layer, such as a zinc oxide layer, on thesubstrate 801. Thereby, a TCO layer, which can be textured in the subsequent processing step such as a wet etching step, is deposited over the substrate. - As shown in
FIG. 10 ,nozzles 842 for spraying a detergent on thesubstrate 801 can be provided in the first chamber of thechambers 830. According to alternatives embodiments, the cleaning step with a detergent can also be conducted in a bath. The substrate or the layer stack being cleaned in the left chamber of thesystem 800 shown inFIG. 8 , is conditioned with alkali metal seeds or an alkali metal seed layer, is transported towards the second andthird chamber 830, whereby for example a drying process might be conducted, and is transferred into thesecond chamber 830. The second chamber includes sputteringcathodes 852, such as rotatable sputtering cathodes, for sputtering. For example, a barrier layer such as a SiON barrier layer, which can be reactively sputtered, can be provided on the conditioned substrate in thesecond chamber 930. Therefater, the TCO layer, such as a zinc oxide layer, is DC sputtered on the barrier layer. Thereby, a TCO layer, which can be textured in the subsequence processing step such as a wet etching step, is deposited over the substrate. - As described above, the
systems
In light of the above, a plurality of embodiments has been described. According to one embodiment, a method of depositing a TCO layer on a substrate is provided. The method includes providing a glass substrate having a first alkali metal concentration, conditioning the glass substrate, wherein the conditioning comprises at least one step selected from the group consisting of: applying a liquid to the substrate to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a layer to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a TCO layer overthe conditioned substrate. According to modifications thereof, the cleaning can further include partly removing contaminants to expose alkali metal-containing seeds of the seed layer, and/or cleaning the glass substrate with a detergent-containing alkali metal-containing seeds; the alkali metal-containing seed layer can be formed on the glass substrate; and/or the method can further includes etching the TCO layer, wherein the etching is adapted to texture the TCO layer. According to yet further embodiments, which can be combined with other embodiments described herein, the TCO layer can be a ZnO-containing layer; the method can further include depositing a barrier layer between the conditioned glass substrate and the TCO layer, particularly wherein the barrier layer is a SiON containing layer; and/or the method can further include polishing the glass substrate before conditioning the glass substrate. According to yet further implementations, which can be combined with other modifications described herein, the number of alkali metal atoms is increased by at least 50%, typically by at least 100%.For example, the number of at least one element selected from the group of: sodium and potassium is increased. - According to another embodiment, a method of manufacturing a precursor for a solar cell is provided. The method includes depositing a TCO layer on a substrate according the embodiments described herein, depositing a layer stack including at least one p-n-junction over the TCO layer, and depositing a back contact layer.
- According to yet another embodiment, a precursor for a solar cell is provided. The precursor includes a glass substrate, a alkali metal-containing seed layer provided on the glass substrate, and a TCO layer deposited over the seed layer. According to modifications thereof, the precursor can further include at least one p-n-junction having several doped semiconductor material layers and a back contact layer. According to yet further additional or alternative modifications, the alkali-metal-containing seed layer can include at least one element selected from the group consisting of Na, K and mixtures thereof; the alkali-metal-containing seed layer can have a thickness of less than 1 nm; the glass substrates can have a first alkali metal concentration within the glass material and the seed layer can have an second alkali metal concentration higher than the first alkali metal concentration; and/or the alkali-metal-containing seed layer can include a number of alkali metal atoms of 1x1013 to 1x1018 atoms per cm2.
- Aside from the better light scattering properties after etching, the improved nucleation of the ZnO can also lead to a higher conductivity and reduced absorption since the overall film quality is improved
- While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.
Claims (15)
- A method of depositing a TCO layer on a substrate, the method comprising:providing a glass substrate (102; 801) having a first alkali metal concentration;conditioning the glass substrate, wherein the conditioning comprises at least one step selected from the group consisting of: applying a liquid to the substrate to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration, and depositing a layer to form a layer with a second alkali metal layer concentration higher than the first alkali metal concentration; anddepositing a TCO layer (104; 204; 404; 604) over the conditioned substrate.
- The method according to claim 1, wherein the cleaning further comprises:partly removing contaminants to expose alkali metal-containing seeds of the seed layer, and/or cleaning the glass substrate with a detergent-containing alkali metal-containing seeds.
- The method according to any of claims 1 to 2, wherein the alkali metal-containing seed layer is formed on the glass substrate.
- The method according to any of claims 1 to 3, further comprising:etching the TCO layer, wherein the etching is adapted to texture the TCO layer (414; 614).
- The method according to any of claims 1 to 4, wherein the TCO layer is a ZnO-containing layer.
- The method according to any of claims 1 to 5, further comprising:depositing a barrier layer (402) between the conditioned glass substrate and the TCO layer, particularly wherein the barrier layer is a SiON containing layer.
- The method according to any of claims 1 to 6, further comprising:polishing the glass substrate (102; 801) before conditioning the glass substrate.
- The precursor according to any of claims 1 to 7, wherein the number of alkali metal atoms is increased by at least 50%, typically by at least 100%.
- A method of manufacturing a precursor for a solar cell, the method comprising:depositing a TCO layer on a substrate according to any of claims 1 to 8,depositing a layer stack (126, 112, 128; 220) including at least one p-n-junction over the TCO layer, anddepositing a back contact layer (124; 218).
- A precursor for a solar cell, comprising:a glass substrate (102; 801);a alkali metal-containing seed layer provided on the glass substrate; anda TCO layer (104; 204; 404; 604) deposited over the seed layer.
- The precursor according to claim 10, further comprising:at least one p-n-junction (126, 128; 220) having several doped semiconductor material layers; anda back contact layer (124; 218).
- The precursor according to any of claims 10 to 11, wherein the alkali-metal-containing seed layer comprises at least one element selected from the group consisting of Na, K and mixtures thereof.
- The precursor according to any of claims 10 to 12, wherein the alkali-metal-containing seed layer has a thickness of less than 1 nm.
- The precursor according to any of claims 10 to 13, wherein the glass substrates (129; 801) has a first alkali metal concentration within the glass material and the seed layer has an second alkali metal concentration higher than the first alkali metal concentration.
- The precursor according to any of claims 9 to 14, wherein the alkali-metal-containing seed layer comprises a number of alkali metal atoms of 1x1013 to 1x1018 atoms per cm2.
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EP10169889A EP2408023A1 (en) | 2010-07-16 | 2010-07-16 | Thin-film Solar Fabrication Process, Deposition method for TCO layer, and Solar cell precursor layer stack |
US12/840,061 US20120012172A1 (en) | 2010-07-16 | 2010-07-20 | Thin-film solar fabrication process, deposition method for tco layer, and solar cell precursor layer stack |
CN2011102064945A CN102339900A (en) | 2010-07-16 | 2011-07-18 | Thin-film solar fabrication process, deposition method for TCO layer, and solar cell precursor layer stack |
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EP10169889A EP2408023A1 (en) | 2010-07-16 | 2010-07-16 | Thin-film Solar Fabrication Process, Deposition method for TCO layer, and Solar cell precursor layer stack |
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US9837565B2 (en) | 2012-12-21 | 2017-12-05 | Flison Ag | Fabricating thin-film optoelectronic devices with added potassium |
US10109761B2 (en) | 2014-05-23 | 2018-10-23 | Flisom Ag | Fabricating thin-film optoelectronic devices with modified surface |
US10396218B2 (en) | 2014-09-18 | 2019-08-27 | Flisom Ag | Self-assembly pattering for fabricating thin-film devices |
EP3582276A1 (en) * | 2018-06-13 | 2019-12-18 | Armor | Film for photovoltaic cell, method for manufacturing same, associated photovoltaic cell and photovoltaic module |
US10651324B2 (en) | 2016-02-11 | 2020-05-12 | Flisom Ag | Self-assembly patterning for fabricating thin-film devices |
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US9837565B2 (en) | 2012-12-21 | 2017-12-05 | Flison Ag | Fabricating thin-film optoelectronic devices with added potassium |
US10153387B2 (en) | 2012-12-21 | 2018-12-11 | Flisom Ag | Fabricating thin-film optoelectronic devices with added potassium |
US10109761B2 (en) | 2014-05-23 | 2018-10-23 | Flisom Ag | Fabricating thin-film optoelectronic devices with modified surface |
US10431709B2 (en) | 2014-05-23 | 2019-10-01 | Flisom Ag | Fabricating thin-film optoelectronic devices with modified surface |
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US10658532B2 (en) | 2016-02-11 | 2020-05-19 | Flisom Ag | Fabricating thin-film optoelectronic devices with added rubidium and/or cesium |
US10971640B2 (en) | 2016-02-11 | 2021-04-06 | Flisom Ag | Self-assembly patterning for fabricating thin-film devices |
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US20120012172A1 (en) | 2012-01-19 |
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